Method of decorating textile fabrics



Patented Nov. 19, 1940 PATENT OFFICE METHOD OF DECORATING TEXTILE FABRICS Henry Jenett, Harrington Park, N. 1., assignor to Interchemical Corporation, New York, N. Y., a

corporation of Ohio No Drawing. Original application June 22, 1939,

Serial No. 280,517.

Divided and this application January 20, 1940, Serial No. 314,868

6 Claims.

This invention relates to an improvement in the art of textile printing.

Conventional textile printing is ordinarily done with water solutions of dyestuflfs containing water soluble thickening agents in suflicient quantity to retard the spreading of the color on the fabric after printing. The dyestufi is fixed onto the fabric by some chemical process and the thickening agent is then washed out of the fabric. The time and expense involved in this after treatment, added to the originally high color cost for light and tub-fast dyes, has been a major problem in textile printing. An unsolved problem has been the reproduction of very fine designs. Since the pastes spread on the fabric after printing when thin enough to be removed sharply from fine engravings, giving blurred designs, it has been found impossible to use photogravure cylinders or extremely fine mill and dye engravings. Attempts to modify these pastes by addition of wetting agents and emulsification of oils therein have not solved the basic difilculties.

The use as printing pastes of colored lacquers (which, for the purpose of this application are defined as dispersions of color in vehicles consisting of a solution of a plastic or solid film forming, water resistant binder such as a cellulose derivative or a resin, in an organic solvent or mixture of solvents) has been attempted in order to overcome the diillculties with prior art pastes, but has not been successful commercially. Relatively few lacquer compositions withstand both dry cleaning and washing; and such compositions as are resistant have been generally unacceptable due to the fact that the fabrics, when printed with these lacquers, develop an undesirable stifl feel (known to the trade as hand") to the necessity for using large amounts of color to obtain deep shades, and to the tendency of colored markings to rub off onto other clothing and leave a mark (known as crocking).

I have invented a new method of textile printing involving the introduction of a new type of textile printing paste which eliminates the disadvantages of the conventional dye printing pastes and avoids the difllculties which have been encountered in the prior art lacquer printing pastes. My new pastes are emulsions in which an outer continuousr.water-immiscible-lacquer phase is thickened by an inner aqueous phase which is at least 20 per cent. of the total emulsion, by weight. Preferably, the binder of the lacquer is one which is originally soluble in ordinary organic solvents and which can be converted 6 into an insoluble state after printing-most desirably, a readily heat-polymerizable synthetic resin, best exemplified by the plasticized. urea formaldehyde resin.

The use of pasteslin accordance with my in- 10 vention permits of the use of cheap pigments and avoids the after treatment necessary with conventional printing pastes. Furthermore, my new pastes separate sharply even from very fine photogravure cylinders, although thickened sufliciently to prevent any spreading on the fabric; this makes possible much finer printing than can be obtained with conventional pastes. The hand imparted to fabrics by my new pastes is very much less than the hand imparted to similar fab a rics by ordinary lacquer pastes having the same binder, the amount of color needed to produce deep shades is sharply reduced, and the crocking substantially eliminated.

I believe that the improved results obtained with my pastes are due to the fact that the color does not penetrate into the fabric or spread laterally on the fabric, so that the bulk of the color remains visible, cemented by binder to the structural fibres of the individual yarns of the fabric, as discontinuous markings at or near the surface of the fabric. Thus, the excessive cementing of fibres and yarns, and the dilution of pigment value characteristic of ordinary lacquer pastes, are both avoided, and hand, pigment cost a and cracking are sharply reduced.

A further advantage of my invention lies in the fact that the use of water to thicken the lacquer sharply reduces the amount of binder required as well as the amount of pigment, so 0 that excessive hand imparted by mere added weight is avoided. In general, I prefer'to maintain the binder content at not above 25%, to minimize weighting of the fabric, and to maintain the volume ratio of binder to pigment at 45 2 to 1 or higher, to minimize cracking. Although good resultsare obtainable with 20% water, I

prefer to operate in the range of 40 to water content. Larger amounts can be added if desired, but care must be taken not to add so 50 7 Example 1 A printing paste is prepared as follows:

10.0 Parts by weight of hydrophobe urea formal- 15 dehyde resin solution (50% resin, 30%

butanol, 20% xylol) I V 15. Parts by weight of alkyd resin (mixed ester of glycerol, phthalic anhydride and soya bean oil fatty acid corresponding to 25% 20 glycerol phthalate and 75% soya bean oil) 17.0 Parts by weight of turpentine substitute (petroleum hydrocarbon) are stirred together to form the lacquer base.

26 10.0 Parts by weight of copper phthalocyanine blue pulp (20% pigment, 80% water) are let down with 48.0 Parts by weight. of water w and stirred into the lacquer phase ina turbo mixer at a relatively high speed, and the mix is then passed through a colloid mill or homogenizer.

' Theresultant emulsion, although it contains only 22% solids, has a consistency like that of value. Because of the consistency of the emulsion, the film produced does not completely surround the individual fibers, but is confined largely to the portions of the fibers adjacent .the

printed side. .In ordertodevelop maximum resistance to washing and dry cleaning in this type of paste containing a heat convertible resin, the

fabric. should be heated to set the resin. This may be done by passing the fabric oyer theconvention'al heating drums used in textile plants, at a temperature of 250 to 300 F.

Some pigments such as the light chrome yellows and certainorganic lakes precipitated on emulsions. I find that this may becorrected by the inclusion of small percentages of colloidal clay, such as bentonite; these additions tend to stabilize the emulsions.

While stable emulsions can be made in a mixer alone, the use of a colloid mill gives a smoother, more desirable product. Where hydrophobe binders are used, while it is preferable to add 95 the water to the lacquer phase, the order may be reversed; in such event, precipitation occurs initially, until sufliclent lacquer is added, when the lacquer coalesces to form a continuous phase.

My invention, while it is of special value with 7 respect to the production of permanent prints on fabric, may also be used for cheaper work, where prior art lacquer prints have been too expensive, by using pastes with very small percentages of pigment and binder. A typical example of this use is the following:

the conventional dye-pastes used for textile alumina hydrate tend to cause breaking of the Imam 2 y A very cheap paste can be made as follows: A lacquer phase of- 4. 5 Parts by weight dewaxed dammar gum 3. 5 Parts by weight xylol 5 19. 0 Parts by weight kerosene and a water phase of 7.5 Parts by weight barium lithol toner pulp pigment, 80% water) let down with 65. 6 Parts by weight water I are mixed as described above, to produce a textile printing paste containing only 6% binder and pigment which has the desired consistency 15 of soft cold cream. This paste may be used where unusual flexibility and resistance to dry cleaning are non-essentials. Such low solid emulsions, when made with flexible film forming ingredients as described in Example 1, are highly 2o desirable in the printing of very sheer fabrics.

Printing pastes made from any water-insoluble resins which may be rapidly converted to films which have the desired resistance to'washing and/or dry cleaning may be used to produce water-in-lacquer emulsions for the best textile printing. While plasticized urea formaldehyde resins give the most satisfactory results, some phenolic resins, and some drying oil modified alkyd resins, have proven acceptable; These are 80 resins of the class specified as preferable and most desirable on page 1, namely, readily heatpolymerizable synthetic resins which can be converted into an insoluble state after printing by heat-polymerization. These resins may be plasticized, as with fatty oils, the.various chemical plasticizers which are water immiscible, and with alkyd resins. Practically all pigments may be used, including metallic pigments previously dispersed in hydrophobe solvents. 40

In'the use of my printing pastes, I prefer to heat the printed cloth to a degree suillcient to convert the resinous binder used to the insoluble state.

The particular printing. pastes described herein are not claimed in the present application as they form the subject matter of my co-pending application ,Serial Number 280,517, filed June 22, 1939, as a continuation. in part of my co-pending application Serial Number 182,795, filed December 31, 1937. The present-application is a division of said application Serial Number 280,517.

I claim:

1. The method of decorating textiles which consists in applying to an intaglio plate a printing paste consisting, essentially of an emulsion of printable consistency containing coloring matter and containing a continuous water-immiscible lacquer phase and a dispersed aqueous phase, 0 and printing upon a textile fabric from said intaglio plate.

2. The method of decorating textiles with a surface decoration which consists in applying to an intaglio plate a printing paste consisting esg5 sentially of an emulsion having a continuous water-immiscible lacquer phase containing coloring material bodied to printable consistency by a disperse aqueous phase comprising at least 20% by weight of the paste, and printing upon '[0 a textile fabric from said intaglio plate.

3. The improvement in the art of textile printing, which consists in thickening the colors printed on an absorbent textile by the emulsification of a thin aqueous liquid in a thin non- 1 emulsion having a continuous, thin, water-immiscible, lacquer phase containing the pigment,

bodied to printable consistency by a dispersed aqueous phase. 1

6. The improvement in the art of textile printing, which consists in filling the engraved lines of. an intaglio. plate with a colored paste whose vehicle consists of thin aqueous and non-aqueous liquids stiffened to printing consistency by emulsiflcation of the aqueous liquid in the non-aqueous liquid, and printing upon an absorbent textile fabric from said intaglio plate.

HENRY JENE'IT. 

